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world Economy & China 2001年第4期9卷 52-58页

作者： louis t.w.cheng Associate Professor of Finance

Does supplier concentration matter to investors during the COV1D-19 crisis:evidence from China?

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Financial Innovation 2022年第1期8卷 2289-2316页

作者： louis t.w.cheng Jack S.C.Poon Shaolong tang Jacqueline wenjie wang School of Business The Hang Seng University of Hong KongHong KongChina School of Accounting and Finance of the Hong Kong Polytechnic University Hong KongChina Division of Business and Management Beijing Normal University-Hong Kong Baptist UniversityUnited International CollegeZhuhaiChina

the literature shows that investor attention to customer–supplier disclosure increases when suppliers’information arrival is *** to the widespread of city lockdowns in China and the implementation of social distancing to control the COVID-19 pandemic,investor attention to potential disruption of the supply chain spikes,leading to a price devaluation for firms with high supplier concentration *** find that a higher degree of supplier concentration is related to more serious stock price declines over the short-term and medium-term windows right after the wuhan *** result lends support to the argument that the concentration risk of suppliers is a significant consideration for China stock market investors,especially under the potential financial distress at the firm level induced by the COVID-19 crisis.

关键词： COVID-19 Supplier concentration Supplier disclosure Stock price effect Industry neutral portfolio

the use of woods-run chips in filter socks to control erosion and sedimentation during petroleum development in the Appalachian Basin

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International Journal of Sediment Research 2019年第6期34卷 608-615页

作者： Shawn t.Grushecky louis M.McDonald Lawrence Osborn west Virginia University Davis College of Agriculture Natural Resources and Design School of Natural Resources Appalachian Hardwood Center at west Virginia University School of Natural Resources Energy Land Management 3. Division of Plant and Soil SciencesEnvironmental Soil Chemistry and Soil Fertility

Filter socks frequently are used for erosion and sediment perimeter control during oil and gas development activities in the Appalachian Basin of the United *** specify the use of composted wood material for sock *** specification,as opposed to non-composted or fresh wood chips(woods-run),has created inefficiencies during well site *** than use fresh wood chips created during site construction,composted chips must be procured and used as filter sock media for erosion and sedimentation *** woods-run chips could be used as filter sock media instead of composted chips,there could be a significant reduction in energy/capital costs,truck traffic,and disposal *** primary objective of this research project was to compare the effectiveness of woodsrun material versus traditionally composted wood chips in controlling sediment transport as well as other chemical and physical parameters in a laboratory *** significant differences in pH(5.96 versus 6.02) or conductivity(0.029 dS/m versus 0.035 dS/m) were found in sediment laden water filtered through woods-run versus composted chips,***,chip particle sizes were outside the allowable limits for composted sock media,and moisture content also was outside the specified limits for woods-run ***(NO) concentrations were significantly higher in woods-run,while phosphorus(P) and potassium(K) concentrations were greater in composted chips;however none of the N,P,or K concentrations were above the regulatory ***,no difference in the filtering efficiency or time was found between woods-run and composted *** laboratory results indicate that current regulations allowing the use of woods-run chips in all but the highest quality watersheds is justified.

关键词： BMP Filter socks Petroleum exploration Marcellus shale wood chips

Modeling the antigen recognition by B-cell and t-cell receptors through thermostatted kinetic theory methods

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International Journal of Biomathematics 2017年第5期10卷 263-299页

作者： Carlo Bianca louis Brezin Laboratoire de Recherche en Eco-innovation Industrielle el Energetique ECAM-EPMI 13 Boulevard de l'Hautil 95092 Cergy Pontoise Cedex France Laboratoire de Physique Statistique Ecole Normale Supdrieure PSL Research University Universite Paris Diderot Sorbonne Paris-Cite Sorbonne Universites UPMC Univ Paris 06 CNRS 24 rue Lhomond 75005 Paris France Institut Universitaire de Cancdrologie Facultg de Medecine Universite Pierre et Marie Curie-Paris 6 91 Bd de l'Hopital 75013 Paris France

the activation and the resulting response of the immune system to antigens comprise different complex processes and cells. this paper aims at modeling the processes of recognition and learning of the immune system by means of the thermostatted kinetic theory methods. Specifically, the thermostatted kinetic framework is firstly generalized for taking into account that in some processes of proliferation of the cells, the rate is also function of the degree of information exchanged amongst cells. In particular, within the new framework, a mathematical model is proposed for miming the recognition process of the immune system through the definition of interactions between the cytoto^ic and humoral components of the adaptive immune system via t- and B-cells. the model validation is obtained by performing a sensitivity analysis on the parameters which depicts the main emerging phenomena and the different phases of the recognition and learning of the immune system.

关键词： thermostatted kinetic theory integro-differential models learning and memory biological complexity immune system.

Orchestration of occludins, claudins, catenins and cadherins as players involved in maintenance of the blood-epididymal barrier in animals and humans

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Asian Journal of Andrology 2007年第4期9卷 463-475页

作者： Daniel G. Cyr Mary Gregory Evemie Dube Julie Dufresne Peter t. K. Chan louis Hermo INRS-Institut Armand Frappier Universite du Quebec 245 Hymus Boulevard Pointe Claire QC H9R 1G6 Canada Department of Urology Royal Victoria Hospital McGill University Montreal QC H3A 1A1 Canada Department of Anatomy and Cell Biology McGill University Montreal QC H3A 2B2 Canada

Although spermatozoa are formed during spermatogenesis in the testis, testicular spermatozoa are immature and cannot swim or fertilize. these critical spermatozoal functions are acquired in the epididymis where a specific luminal environment is created by the blood-epididymal barrier; proteins secreted by epididymal principal cells bind to maturing spermatozoa and regulate the maturational process of the spermatozoa. In the epididymis, epithelial cell-cell interactions are mediated by adhering junctions, necessary for cell adhesion, and by tight junctions, which form the blood-epididymal barrier. the regulation of these cellular junctions is thought to represent a key determinant in the process of sperm maturation within the epididymis. tight junctions between adjacent principal cells permit the formation of a specific microenvironment in the lumen of the epididymis that is essential for sperm maturation. Although we have made significant progress in understanding epididymal function and the blood-epididymal barrier, using animal models, there is limited information on the human epididymis. If we are to understand the normal and pathological conditions attributable to human epididymal function, we must clearly establish the physiological, cellular and molecular regulation of the human epididymis, develop tools to characterize these functions and develop clinical strategies that will use epididymal functions to improve treatment of infertility. （Asian J Androl 2007 July; 9： 463- 475）

关键词： claudins cadherins catenins human rat mouse tight junction adherens junction

Ru complex and N,P-containing polymers confined within mesoporous hollow carbon spheres for hydrogenation of CO_(2)to formate

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Nano Research 2023年第4期16卷 4515-4523页

作者： Guoxiang Yang Yasutaka Kuwahara Kohsuke Mori Catherine louis Hiromi Yamashita Division of Materials and Manufacturing Science Graduate School of EngineeringOsaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan Institute for Open and transdisciplinary Research Initiatives(OtRI) Osaka University2-1 Yamada-okaSuitaOsaka 565-0871Japan Unit of Elements Strategy Initiative for Catalysts&Batteries(ESICB) Kyoto UniversityKatsuraKyoto 615-8520Japan JSt PRESTO4-1-8 HonchoKawaguchiSaitama 332-0012Japan Sorbonne Université CNRSLaboratoire de Réactivitéde SurfaceLRSF-75005 ParisFrance

the development of reliable catalysts with both excellent activity and recyclability for carbon dioxide(CO_(2))hydrogenation is ***,a ternary hybrid heterogeneous catalyst,involving mononuclear Ru complex,N,P-containing porous organic polymers(POPs),and mesoporous hollow carbon spheres(Ru^(3+)-POPs@MHCS)is reported for CO_(2)hydrogenation to *** on comprehensive structural analyses,we demonstrated that Ru^(3+)-POPs were successfully immobilized within *** optimized Ru^(3+)-0.5POPs@MHCS catalyst,which was obtained with about 5 wt.%Ru^(3+)and 0.5 mmol POPs polymers confined into 0.3 g MHCS,exhibited high catalytic activity for CO_(2)hydrogenation to formate(turnover number(tON)>1,200 for 24 h under mild reaction conditions(4.0 MPa,120℃))and improved durability,compared to Ru^(3+)catalysts without POPs polymers(Ru^(3+)-MHCS)and unencapsulated MHCS(Ru^(3+)-0.5POPs)*** improved catalytic performance is attributed to the high surface area and large pore volume of MHCS which favors dispersion and stabilization of Ru^(3+)-***,the MHCS and POPs showed high CO_(2)adsorption ***^(3+)-POPs encapsulated into MHCS reduces the activation energy barrier for CO_(2)hydrogenation to formate.

关键词： heterogeneous catalysis porous organic polymers(POPs) mesoporous hollow carbon spheres CO_(2)hydrogenation formate synthesis

toll-like receptor 2-mediated NF-kappa B pathway activation in ocular surface epithelial cells

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Eye and Vision 2017年第1期4卷 93-99页

作者： Aihua Hou Min Qi tin louis tong Ocular Surface Research Group Singapore Eye Research InstituteSingaporeSingapore Duke-NUS Graduate Medical School SingaporeSingapore Singapore National Eye Center SingaporeSingapore Yong Loo Lin School of Medicine National University of SingaporeSingaporeSingapore

Background:Gram-positive bacteria stimulate toll-like receptor(tLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)*** the human ocular surface is heavily colonised by gram-positive cocci bacteria,a balance of activation/repression of NF-κB target genes is essential to avoid uncontrolled infection or autoimmune-related *** is advantageous to test NF-κB targeting molecules in an ocular surface culture system that allows assessment of temporal NF-κB activation in a longitudinal fashion without destruction of *** initial testing under standardised conditions should reduce the number of molecules that progress to further evaluation in animal *** study aims to establish an in-vitro cell culture system to assess NF-κB activation in the context of ocular surface ***:NF-κB activity was evaluated through a secretory alkaline phosphatase reporter assay(SEAP).Immunoblots and immunofluorescence were used to examine IκBαphosphorylation and p65/p50 nuclear *** chemoattractant protein-1(MCP-1)transcripts were evaluated by real time PCR and protein levels were measured by ***:NF-κB activity in HCE-t cells treated with tLR2 activator Pam3CSK4 was higher than control cells at both 6 and 24 ***3CSK4-stimulated NF-κB activation was inhibited by IκK inhibitors,wedelolactone and *** Pam3CSK4 treated cells,active NF-κB subunits p50 and p65 increased in cell nuclear fractions as early as 1.5 *** the level of total IκB-αremained constant,phospho-IκB-αincreased with treatment over *** the culture media of Pam3CSK4-stimulated cells,MCP-1 protein level was increased,which was suppressed in the presence of IκK ***:NF-κB pathway can be activated by the tLR2 ligand and inhibited by IκK inhibitors in the ocular surface cell culture *** cell culture system may be used to evaluate tLR-related innate defences in ocular surface diseases.

关键词： tLR2 NF-κB pathway Activation Ocular surface cells

Representation of A15 composition and t_C in internal-Sn Nb_3Sn superconducting strands

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Science China(technological Sciences) 2010年第11期53卷 3020-3026页

作者： Andre SULPICE Jean-louis SOUBEYROUX Christophe VERwAERDE Gia Ky HOANG NEEL/CNRS-UJF ALStOM 3 bis avenue des 3 Chenes 90018 Belfort France

Four sets of mono-element (ME) and two kinds of multifilament (MF) internal-Sn Nb3Sn superconducting strands were designed and fabricated through RRP method in which different compoment ratios, various composite configurations and some third element alloying were arranged. All the strand samples underwent a 210°C/50 h + 340°C/25 h thermal duration for Cu-Sn alloying. After that A15 phase formation heat treatment (Ht) was applied for which the ME samples were chosen at three reaction temperatures of 675°C, 700°C and 725°C for 100 h and 200 h while the MF samples at four temperatures of 650°C, 675°C, 700°C and 725°C for 128 h and 200 h. the heat-treated samples were examined for A15 phase composition distribution by X-ray EDS. SQUID magnetization measurement was used to determine critical temperature tC. the obtained results demonstrate that for fully-reacted internal-Sn Nb3Sn superconductors the A15 phase composition and the intrinsic property tC are determined by the diffusion and solid state reaction mechanism and are independent of the factors including Ht temperature, strand composite component and configuration arrangement, and the third element addition within the experimental range.

关键词： internal-Sn Nb3Sn strands A15 phase composition phase formation heat treatment composite configuration and design third element alloying

Model-based estimation of above-ground biomass in the miombo ecoregion of Zambia

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Forest Ecosystems 2016年第4期3卷 258-274页

作者： James Halperin Valerie LeMay Emmanuel Chidumayo louis Verchot Peter Marshall Department of Forest Resources Management The University of British Columbia 2424 Main Mall Vancouver BC V6T 1Z4 Canada Makeni Savanna Research Project P.O. Box 50323 Ridgeway Lusaka Zambia International Center for tropical Agriculture Km 17 Recta Cali-Palmira Apartado Aereo 6713 Cali 763537. Colombia

Background：Information on above-ground biomass（AGB） is important for managing forest resource use at local levels,land management planning at regional levels,and carbon emissions reporting at national and international *** many tropical developing countries,this information may be unreliable or at a scale too coarse for use at local *** is a vital need to provide estimates of AGB with quantifiable uncertainty that can facilitate land use management and policy development ***-based methods provide an efficient framework to estimate ***：Using National Forest Inventory（NFI） data for a^1,000,000 ha study area in the miombo ecoregion,Zambia,we estimated AGB using predicted canopy cover,environmental data,disturbance data,and Landsat 8 OLI satellite *** assessed different combinations of these datasets using three models,a semiparametric generalized additive model（GAM） and two nonlinear models（sigmoidal and exponential）,employing a genetic algorithm for variable selection that minimized root mean square prediction error（RMSPE）,calculated through *** compared model fit statistics to a null model as a baseline estimation *** bootstrap resampling methods,we calculated 95% confidence intervals for each model and compared results to a simple estimate of mean AGB from the NFI ground plot ***：Canopy cover,soil moisture,and vegetation indices were consistently selected as predictor *** sigmoidal model and the GAM performed similarly;for both models the RMSPE was -36.8 tonnes per hectare（i.e.,57% of the mean）.However,the sigmoidal model was approximately 30% more efficient than the GAM,assessed using bootstrapped variance estimates relative to a null *** selecting the sigmoidal model,we estimated total AGB for the study area at 64,526,209 tonnes（＋/- 477,730）,with a confidence interval 20 times more precise than a simple designbased ***：Our findings demonstrate that NFI

关键词： National Forest Inventory Above-ground biomass Miombo REDD+ Generalized additive model Nonlinear model Landsat 8 OLI

Presence of extensive intraductal component in patients undergoing breast conservative surgery predicts presence of residual disease in subsequent completion mastectomy

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Chinese Medical Journal 2009年第8期122卷 900-905页

作者： Christopher C. E Yiu wings t. Y. Loo C. K. Lam louis w. C. Chow UNIMED Medical Institute Comprehensive Centre for Breast Diseases Hong Kong China Clinical trial Centre Li Ka Shing Faculty of Medicine University of Hong Kong China

Background Local recurrence remains a serious problem among patients undergoing breast conservative surgery. this study aimed at identifying risk factors for residual disease after breast conservative surgery. Methods this retrospective study was based on patients with invasive breast cancer who have received breast conservative surgery and subsequent completion mastectomy. All patients had a clear resection margin in the initial operation. we analyzed the association between the presence of residual disease during completion mastectomy and the following risk factors： t staging, young age, and presence of extensive intraductal component （EIC）, a close margin, lymphovascular permeation （LVP）, positivity of estrogen receptor, progesterone receptor, and c-erbB-2. Results Residual disease was encountered in 21 （45.7%） of 46 patients; EIC was present in 28 patients （60.9%）, of whom 17 had residual disease. Presence of EIC during breast conservation surgery was associated with a higher risk of residual disease during completion mastectomy （P=0.011）. Other variables were not statistically significant risk factors for presence of residual disease. No local recurrence was recorded in our cohort, and the disease-free survival and overall survival after completion mastectomy were similar for patients who had residual disease and those who had not. Conclusions the presence of EIC is a significant risk factor for residual disease in patients after breast conservative surgery. Our findings may suggest the indicated value of completion mastectomy in patients with EIC during initial breast conservative surgery to decrease the risk of subsequent local failure.

关键词： extensive intraductal component breast conservative surgery residual disease completion mastectomy